On Apr 4, 2006, at 5:52 PM, Cyp her wrote:
* What is the best way of retrieving the session context
(DataContext) on a given page and tracking the changes over a
workflow and eventually committing the changes or discarding them?
Cayenne 1.2 has a WebApplicationContextFilter:
http://objectstyle.org/confluence/display/CAYDOC/Servlet+2.3+Filter
It provides you access to the session DataContext regardless of the
framework you use (in the past I put it in Tapestry Visit instead,
but I don't bother anymore, the filter is more portable). If you
configure the filter per docs page above, you can always get the
session context anywhere in the app like this:
DataContext context = DataContext.getThreadDataContext();
* I have read some people opt to use Tapestry, Spring and
Hibernate. What are the advantages if there are any and can you use
Tapestry, Spring and Cayenne?
Yeah, that's the right place to ask for an unbiased Cayenne vs.
Hibernate comparison ;-)
Hibernate is an ORM, so conceptually it is similar to Cayenne (and
EOF). Regarding the differences... Cayenne provides more EOF-like
experience in managing your object graph. I've heard an opinion from
a WO user that Hibernate is more like eoaccess (I guess he was
referring to the fact that you need to manage a number of low-level
details). In this respect Cayenne is eoaccess+eocontrol (and since
recently - also EO JavaClient, for those who care). DataContext is
very similar to EOEditingContext.
IMO when migrating from WO, switching from EOF to Cayenne is a
relatively minor thing compared to switching WO framework to any
other web front-end technology.
Andrus
